1/xy+1/(x+1)(y+1)+1/(x+2)(y+2)+···+1/(x+2012)(y+2012)
=1/1x2+1/2x3+1/3x4+...+1/2013x2014
=1-1/2+1/2+1/3+1/3-1/4+...+1/2013-1/2014
=1-1/2014
=2013/2014
若x=1,y=2,求1/xy+1/﹙x+1﹚·﹙y+1﹚+1/﹙x+2﹚·﹙y+2﹚…………+1/﹙x+2009)·(y+2009)的值
若x=1,y=2,求1/xy+1/﹙x+1﹚·﹙y+1﹚+1/﹙x+2﹚·﹙y+2﹚…………+1/﹙x+2009)·(y+2009)的值
数学人气:131 ℃时间:2020-03-17 23:14:45
优质解答
我来回答
类似推荐
猜你喜欢
- 1光明小学10月用水145吨,11月比10月节约了1/5,11月用水多少吨?
- 2如图,△ABC的周长为32,且AB=AC,AD⊥BC于D,△ACD的周长为24,那么AD的长为_.
- 3有6题有关for及since用法,帮我看一下好吗?
- 4can you ____ him to call me back?sure.a.ask b.make c.let d.hope
- 5热化学方程式中不可以写可逆符号吗
- 6Ask your pen pal to write about herself?
- 7根据上下文意思,将对话中的所缺部分补全,或填单词,或填短语,或填句子,确保对话通顺.
- 8比喻作是力量不够,感到无可奈何意思的成语是什么
- 9100块砖,100人搬,男搬4块砖,女搬3块砖.两个小孩搬1块砖.问男人,女人,小孩各多少
- 10while watching television,__________ A we heard the doorbell ring B wo heard the doorbell rings